This disclosure relates generally to eye tracking in head-mounted displays, and specifically relates to using an infrared transparent backlight device for eye tracking applications in a head-mounted displays.
Some conventional display systems use a separate light source in conjunction with a Backlight Unit (BLU). A BLU typically incorporates different light scattering layers that scatter both visible light and infrared (IR) light. The scattering characteristics of the BLU restrict locations of IR cameras and/or IR sources in head-mounted displays. For example, an IR camera positioned to image an object through a BLU would have poor image quality due to the scattering of IR light caused by the BLU.